Studies come from North Carolina State University, where researchers noticed that children born just before the kindergarten enrollment cutoff date, who are among the youngest in their class, were more likely to be diagnosed with ADHD than their older classmates. The researchers determined this wasn’t a likely coincidence.

"We believe that younger children may be mistakenly diagnosed as having ADHD, when in fact they are simply less mature," lead researcher Dr. Melinda Morrill explained in a university news release cited by MSNBC.

Children diagnosed with ADHD may be more talkative, forgetful, or fidgety, and may have more difficulty playing quietly and taking turns. Frequent daydreaming and disruptive behavior also characterize ADHD.

“We are not downplaying the existence or significance of ADHD in children,” Morrill says. “This indicates that there are children who are diagnosed, or not, because of something other than underlying biological or medical reasons.”

Misdiagnosed ADHD can mask other issues, including learning disorders, hyperthyroidism, Asperger’s syndrome, or other forms autism. According to Mayo Clinic, as many as one in three children diagnosed with ADHD may also have one of these other conditions. The fear is that these conditions may be overlooked and that children may be put on ADHD medication unnecessarily.

Paying close attention to all of your child’s symptoms and making a careful assessment of his or her behavior with your doctor can help avoid misdiagnosis. See the full story from MSNBC.